St Kilda Triathlon Club Coach on Using TrainingPeaks Data to Program an Athlete’s Individual Training

Training Stress Score (TSS) and Chronic Training Load (CTL) are two key metrics in TrainingPeaks that I use as a coach to carefully plan and monitor my athletes' training. Understanding these numbers allows me to strike the perfect balance between training load and recovery, ensuring my athletes stay on track and avoid under or overtraining.

TSS is a measure of the total workload of a training session, calculated based on duration and intensity. Every workout has a TSS value, giving a snapshot of how much stress that session placed on the body. For example, a long, steady ride might accumulate a TSS of 150, while a shorter, high-intensity interval session could also hit 150, reflecting the different pathways stress can accumulate. The key is that TSS quantifies training in a single number, making it easier to compare sessions.

CTL, on the other hand, is a longer-term measure. It represents the rolling average of TSS over a set period, typically 42 days, providing insight into an athlete’s overall fitness. A higher CTL usually means the athlete has been handling a greater training load over time and has built more endurance, strength, or speed depending on their training focus.

As a coach, I use TSS and CTL together to build smart training plans tailored to each athlete. When mapping out a training block, I aim for a progressive increase in CTL, ensuring that each week builds on the last while incorporating lighter weeks to allow for recovery. The goal is a gradual rise in CTL leading up to race day, reflecting increasing fitness.

By tracking TSS for individual sessions, I ensure my athletes are getting the right mix of intensity and volume. For example, if an athlete has a high TSS from a hard interval session on Tuesday, I might schedule an easier endurance ride on Wednesday to avoid overloading their system. Similarly, if I see that weekly TSS is rising too quickly, I know to pull back and prioritise recovery.

One of the most valuable applications of these metrics is race preparation. In the weeks leading up to a race, I use TSS to structure tapering, ensuring the athlete maintains enough training load to stay sharp while gradually reducing stress to arrive at the start line fresh. Monitoring CTL helps me see the big picture, ensuring the athlete's overall fitness is peaking at the right time.

Another crucial metric I monitor alongside TSS and CTL is Acute Training Load (ATL), which measures short-term fatigue. The balance between CTL and ATL gives me the Training Stress Balance (TSB), a predictor of readiness. Positive TSB means the athlete is fresh, while negative TSB indicates fatigue. Managing this balance ensures I can spot when an athlete might be at risk of overtraining or when they’re primed for a peak performance.

In short, TSS and CTL are indispensable tools that allow me to take a data-driven approach to training. They provide a clear view of where my athletes are, where they’re headed, and what adjustments are needed along the way. With these metrics, I can make informed decisions to optimise performance, prevent injury, and help my athletes achieve their goals.

If you wold like to get in touch with St Kilda Triathlon Head Coach Steve Davis, you can click though to the Contact Us page and organise a catch up to see how he can help to improve your overall fitness and triathlon specific skills.